Door closer



Feb. 22, 1955 A. P. MARCUS 2,702,393

DOOR CLOSER Filed May 3, 1954 2 Sheets-Sheet i 1N VEN TOR.

FEE 5 4127mm p, Mq cus Feb. 22, 1955 A. P. MARCUS DOOR CLOSER 2 Sheets-Sfieet 2 Filed May 3, 1954 5 I. Y Z W H m m0 w% m 2 la 4 0 J United States Patent DOOR CLOSER Arthur P. Marcus, Lyndhurst, Ohio Application May 3, 1954, Serial No. 427,038

6 Claims. (Cl. 1666) This invention relates to door hardware and particularly to door closers of the check type, ordinarily used on screen doors or on combination screen and storm doors of private residences, to maintain such doors in a closed position, except when forcibly held open.

Conducive to a better understanding of the invention, it may be well to point out that at present such closers consist of an air cylinder, a plunger, a spring and an adjustable air valve, arranged in various juxtapositions and all intended to close an open door in a quiet manner. The air cylinder, plunger and air valve operate to snub, or arrest, the speed of the closing door as it nears the closed position, thus preventing the slam which occurs when such a door is closed by an unopposed spring.

However, such closers have certain inherent undesirable characteristics, such as requiring rather careful adjustment of the air valve to match the weight of the door; failure of the valve to maintain such adjustment during natural wide changes in ambient temperatures; failure of the air valve due to the accumulation of fore gn matter in the valve aperture; and an insuflicient snubbing action when the door is partially opened and then released.

Accordingly, the primary object of this invention is to provide a door closer having an improved method of operation and to eliminate the adjustable air valve, per se, with its attendant defects.

Another object is to provide a closer that can be used with doors of any weight without requiring adjustment, either at installation or at the time of seasonal change when combination screen and storm doors have their functional parts interchanged.

A further object of this invention is to provide means for attaching a door closer of the type stated, to a wooden door and wooden jamb, such means bemg so arranged as to minimize splitting of the wood by havmg all screw holes so positioned that not more than one screw can be inserted in any one grain stratum or fibrous fissure.

Still another object is to provide a door closer that is economical to manufacture, easy to install and reliable in operation.

These and other objects of the inventlon will become apparent upon a reading of the following specification and claims, together with the accompanying drawings, wherein like parts are referred to and indicated by like reference characters and wherein:

Figure 1 is a top plan view, partly in section, showing a door closer embodying the principal features of this invention;

Figure 2 is an enlarged sectional view of the door bracket end of the closer illustrated in the Figure 1, showing the details of the plunger head assembly;

Figure 3 is a side elevation of the jamb bracket; Figure 4 is a right end view of the same, showing a preferred arrangement of the mounting holes;

Figure 5 is a side elevation of the door bracket; Figure 6 is a right end view of the same, showing a preferred arrangement of the mounting holes;

Figure 7 is a plan view of the closer installed, with the door in its closed position;

Figure 8 is a plan view of the closer installed, with the door in a partly open position, with portions broken away to show the relation of the parts;

:-Figure 9 is a front view of the perforated disk member;

Figure 10 is a vertical sectional view taken along the line and in the direction of the arrows 1010 of the Figure 9;

b F ignrg 11 is a perspective view of the porous disk memer; an

Figure 12 is an enlarged cross-sectional view of the anchor cap end of the tubular member taken along the line and in the direction of the arrows 12-12 of the Figure 1.

ln practicing my invention in its preferred form, there is provided a door bracket to which is pivotally attached the closed and sealed end of an elongated tubular member. A rod about as long as the tubular member is fitted at one end with a plunger comprised of a perforated back follower disc member slightly smaller than the inside tube diameter, a flexible cup shaped member, an optional spring-like cup shaped member and a porous plate member smaller than the inside cup diameter, all securely afiixed to the rod. A ring shaped cap closes the other end of the elongated tubular member. A suitable anti-friction sleeve bearing mounted in the cap supports the rod and a spring member surrounding the rod inside the tube bears against the bearing cap at one end and the back follower disc affixed to the rod at the other end. An optional second spring member smaller in diameter and shorter may also surround the rod inside the first spring member. The end of the rod extending through the bearing cap is pivotally attached to a jamb bracket.

In operation, as the rod is pulled through the bearing cap by opening the door, the first spring member is compressed between the bearing cap and the perforated back follower disc member on the rod. The lip of the flexible cup shaped member moves slightly out of contact with the inside wall, permitting air to flow from the area containing the spring past the cup into the area between the cup and the closed and sealed end of the tube. As the door nears the limit of travel intended, the smaller spring member is also compressed between the bearing cap and the follower disc on the rod, snubbing the door opening movement. As the door is released, the energy stored in the compressed springs moves the plunger toward the closed and sealed end of the tube, compressing the air between that end and the cup. As this air pressure builds up, air flow starts through the porous disc and the perforated follower disc, thereby flowing into the area containing the springs, causing a smooth closing action for the door.

As the porous disc, made of material such as com pressed metal powder sintered to form a rigid mass, contains many small interconnecting air passages, a large number of these passages may accumulate foreign matter without significantly affecting the air flow rate. Furthermore, due to the minuteness of these air passages, the air flow rate is directly proportional to the air pressure, and as the air pressure is directly proportional to the energy remaining stored in the spring, a decreasing rate of travel occurs as the door approaches the closed position. At all positions, the pull on the rod exerted by the spring is balanced by the air pressure, and movement of the rod occurs only as the air pressure is released through the porous disc.

Referring to the drawings, there is illustrated a preferred embodiment of my invention in the form of a door closer that is so constructed as to automatically close a door from any position to which it has been forcibly opened, such closing means employing a porous diaphragm to limit the rate of motion to that which minimizes slam, yet is sufficient to fully and securely close and latch the door. The mounting means are so arranged that in installing on a wooden door and jamb, the attaching screws are positioned so that not more than one screw can be inserted in any one grain stratum 01' fibrous fissure.

The preferred form of the closer illustrated in Figure 1 comprises an elongated tubular air cylinder or shell member 20 which is pivotally attached at one erid to a door bracket 21 through a pintle pin 22 that is journaled in holes 23 in the bracket 21. The bracket 21 has mounting holes 24, non-symmetrically arranged, preferably as 2,7o2,s9s I r 7 in the wood of door 26. The air cylinder or shell is closed at its door bracket engaging end by an air tight anchor cap 27 which is secured in place by three hollow rollpins 28 which pass through the shell wall and seat inblind holes in the cap 27, as is seen most clearly in- Figure 12. A stop 29 is mounted in the center of the cap 27; A'b'earing cap 43 is mounted at the other end of the shell by means of three hollow rollpins 45 which pass the the rod 30 is pivotally attached to jamb bracket 47 by a pintle pin 46 which is seated in vertically aligned holes 48 in the bracket 47. The bracket 47 also has non-symmetrically arranged mounting holes 49, as seen in Figure 4, through which mounting screws 50 pass to setglre same to the door jamb 51, as seen in Figures 7 an 8.

Reference numeral 42 indicates a snubber spring which is used to increase the load rate on the rod 30 when the door 26 is opened beyond a predetermined point. This is desirable to prevent damage, either to the door or closer by enthusiastic opening of the door, such as by children or by the wind.

Referring more particularly to the plunger element, the rod 30 has a shaft portion 40 of reduced diameter at its inner end, as is seen most clearly in 'Figure 2. The follower plate 31 is mounted on the shaft 40 against its shouldered end by means of a central bore 33 which snugly fits the shaft 40. Plate 31 has a plurality of perforations 32 therethrough proximate its central bore 33, as seen in Figures 9 and 10. The diameter of the perforated plate 31 is slightly less than theinside diameter of the shell 20. A flexible cup shaped member 34 is mounted ahead of the plate 31. The cup 34 has .a flexible 'lip around the peripheral edge thereof which contacts the inside wall of the shell 20.

Reference numeral 36 indicates a porous disc preferably made of compressed metal powder, sintered to form a rigid mass having a multitude of interconnecting .air passages therethrough. This disc is made similar to the socalled permanently oiled bearing material, as it is before the oil is aded.

It is, of course, to be understood that any similarly porous material 'may'be used such as porous ceramic material. The porosity and thickness of'the disclis selected to provided the optimum closure action desired. The

porous disc 36 is of smaller diameter than the cup 34 and has a central hub37 which fits into the central opening of the cup, with its front face abutting the perforated area of the plate 31,-as is most clearly seen in Figure:2. The disc 36has a central bore 38by means of .whichit is mounted on the shaft 40.

In cases when the cup lip might not be rigid enough to properly seat againstthe shell wall, ian optional springlike cup shaped member may be inserted between the cup 34 andthe porous disc 36. With the several 'ele- I} ments mounted onthe rodshaft 40,'the end of the shaft is drilled out to form a thin walledend portion which is peened over as at39 to lock the severalelements tightly together on the 'shaft end of the rod 30.

It will now be seen that the shell 20 is divided into two compartments'bythe'porousdisc assembly. When the door '26'is-partia1ly opened to take the position illus 'trated inFigure '8, the movement -'of the door bracket 21 'away'from the jamb bracket 47*causes the rod to move out of the shellj20 through the bearing 44. 'This action moves the piston assembly away from the cap 27, thereby c'reatinga partial vacuum in the air cylinder 20 between the ,cap 27:and the. piston assembly. Theair'on the spring :side of the piston which .is ,at atmospheric pressure presses against the lipof the flexible cup 34 which flexes to permit-iair to pass between the lip and the shell wall into the compartment between the'cap27 and the porous disc 36. As the door continuesnto open, the driver spring 41 which bears against the plate .31. is compressed and stores up tcnergy. As: the door. nears the limit ,of:;travel 4 V intended, the snubber spring 42 is also compressed between the bearing cap 43 and the plate 31, thus greatly increasing the load and bringing the door to a gradual stop, without jerk or strain.

Upon release of the door, the springs 41 and 42 act to push the piston assembly strongly toward the closed cap end 27. This compresses the air ahead of the piston causing the lip of the cup to seal against the shell wall. The air which is now under pressure and trapped between the cap 27 and the disc 36 holds back the piston, and air flow starts through the porous disc and perforated plate into the area or compartment containing the springs. Due to the minuteness of the air passages in the porous disc 31, the air flow rate is directly proportional to the air pressure, and as'the air pressure is directly proportional to the energy remaining stored in the springs, a decreasing rate of travel occurs as the door approaches the closed position. As stated hereinbefore, the pull on the rod 30 exerted by the spring 41 is balanced by the airpres sure and movement of the rod occurs only' as the air pressure is released through the porous disc 36. Creation of sub-atmospheric pressures, which might interfere with the proper operation of the closer, on the spring side of the piston, is prevented by the aforementioned hollow rollpins 45, through which atmospheric air may enter the shell 20.

It will be further apparent that by means of this structure, wherein use is made of a porous diaphragm to control the air flow, the door closer will function in a substantially uniform manner, independent of seasonal changes. It will also be apparent that as transfer of air is largely independent of adverse environmental atmosphere, such as dust; and that such air as may enter the closercannot significantlyaffectits operation, due tothe large number of air passages employed to establish the rate of closing.

Furthermore, it will be clear that there has been provided a door closer of novel and improved design, free from need for adjustment by the purchaser, and operable to close a door of any weight smoothly and firmly from any open position.

The invention further provides a door closer that can be installed on a wooden door and jamb with little chance of splitting the wood, as all mounting screws are so located that each screw engages a separate grain stratum or fibrous fissure.

It will now be clear that there is provided a device which accomplishes the objectives heretofore set forth. While the invention has been disclosed in its preferred form, it is to be understood that the specific embodiment thereof as described and illustrated herein is not to be consideredin a limited sense as theremay be otherforms or modifications of the invention which should also be construed to come within the scope of the appended claims.

1. An automatic door closer, comprising in combination, a door bracket,an elongated tubular air cylinder pivotally attached to said bracket, a plunger rod, having a porous member at its inner end, slidably mounted in the cylinder, a jamb bracket pivotally attached to .said rod, means including a spring urg ng the cylinder toward the jamb' bracket and opposing relative displacement of said cylinder and rod, means for by-passing air aroundthe porous mernber when the cylinderis moving away from the amb bracket, and trapping said by-passed air'behind the porousmernber upon movement of the air cylinder towardtthe 121mb bracket, said porous -member serving to control the rate of air flow therethrough underthe pressure of the spring moving the cylinder-toward the bracket.

2. 'An automatic door closer, comprlsmg in com- 'bination,-a door bracket, .an elongated tubular air cylinder pivotally attached totsaid bracket, a plunger rod, having a porous member at its inner end, slldably mounted in the cylinder, --said-poro'us.member comprising metal powder' s'interedto torm a rigid disc having a multitude of small interconnecting air passages, a

jamb bracket pivotally attached to said rod, means in-' cluding a spring urging the cylinder toward the jamb bracket and opposing relative displacement of said cyl- .inder and rod, means for .by-passing air around the porous member when'the cylinder is moving awayfrom the jamb. bracket, and trapping-sa d by-passed an bebind the porous member upon movement of the air cylinder toward the jamb bracket, said porous member serving to control the rate of air flow therethrough under the pressure of the spring moving the cylinder toward the jamb bracket.

3. An automatic door closer, comprising in combination, a door bracket, an elongated tubular air cylinder pivotally attached to said bracket, a plunger rod, having a porous member at its inner end, slidably mounted in the cylinder, the air cylinder being divided by the porous member into first and second chambers, a jamb bracket pivotally attached to said rod, means including a spring urging the cylinder toward the jamb bracket and opposing relative displacement of said cylinder and rod, means for by-passing air from the first chamber around the porous member into the second chamber, when the cylinder is moving away from the jamb bracket, and trapping said by-passed air in the second chamber behind the porous member upon movement of the air cylinder toward the jamb bracket, said porous member acting to control the rate of the return air flow therethrough from the second chamber to the first chamber under the pressure of the spring mov ing the cylinder toward the jamb bracket.

4. An automatic door closer, comprising in combination, a door bracket, an elongated tubular air cylinder pivotally attached to said bracket, a plunger rod, having a porous member at its inner end, slidably mounted in the cylinder, said porous member comprising metal powder sintered to form a rigid disc having a multitude of small interconnecting air passages, said cylinder being divided by the porous member into first and second chambers, a jamb bracket pivotally attached to said rod, means including a spring urging the cylinder toward the jamb bracket and opposing relative displacement of said cylinder and rod, means for by-passing air from the first chamber around the porous memher into the second chamber, when the cylinder is moving away from the jamb bracket, and trapping said by-passed air in the second chamber behind the porous member upon movement of the air cylinder toward the jamb bracket, said porous member acting to control the rate of the return air flow therethrough from the second chamber to the first chamber under the pressure of the spring moving the cylinder toward the. jamb bracket.

5. An automatic door closer, comprising in combination, a door bracket, an elongated tubular air cylinder pivotally attached to said bracket, a plunger rod, having a porous member at its inner end, slidably mounted in the cylinder, a jamb bracket pivotally attached to said plunger rod, means including first and second springs urging the cylinder toward the jamb bracket and opposing relative displacement of said cylinder and rod, said second spring being operable to greatly increase the load rate when the change in longitudinal relation between the cylinder and rod exceeds a predetermined limit, means for by-passing air around the porous member when the cylinder is moving away from the jamb bracket, and trapping said by-passed air behind the porous member upon movement of the air cylinder toward the jamb bracket, said porous member serving to control the rate of air flow therethrough under the pressure of the spring moving the cylinder toward the jamb bracket.

6. An automatic door closer, comprising in combination, a door bracket, an elongated tubular air cylinder pivotally attached to said bracket, a plunger rod, having a porous member at its inner end, slidably mounted in the cylinder, the air cylinder being divided by the porous member into first and second chambers, a jamb bracket pivotally attached to said plunger rod, means including first and second springs urging the cylinder toward the jamb bracket and opposing relative displacement of said cylinder and rod, said second spring being operable to greatly increase the load rate when the change in longitudinal relation between the cylinder and rod exceeds a predetermined limit, means for by-passing air from the first chamber around the porous member into the second chamber, when the cylinder is moving away from the jamb bracket, and trapping said by-passed air in the second chamber behind the porous member upon movement of the air cylinder toward the jamb bracket, said porous member acting to control the rate of the return air flow therethrough from the second chamber to the first chamber under the pressure of the spring moving the cylinder toward the jamb bracket.

References Cited in the file of this patent UNITED STATES PATENTS 1,464,478 Greenwood Aug. 7, 1923 2,071,660 Schulz Feb. 23, 1937 2,308,404 Thornhill Jan. 12, 1943 

